Method and apparatus for pressurizing steam

ABSTRACT

Steam is taken at a generated pressure e.g. from a desalinization system and is altered in pressure for particular purposes e.g. to feed steam powered turbines at a single step or in multiple stages for example dividing a quantity of steam at an intermediate pressure into higher and lower pressure portions.

United States Patent RH 1 i 1 inventor App]. No. Filed Patented METHOD AND APPARATUS FOR PRESSURIZING Glenn D. James I [56] References Cited 1200 Encino Ave., Arcadia, Calif. 91106 UNITED STATES PATENTS 746,09 2,479,856 8/1949 Mitton My 19,1968 2,532,679 12/1950 Slater r.

2,539,292 1/1951 Anderson..

3,349,995 10/1967 Sheesley......1.,..1 1. 3,362,618 1/1968 Fortinov Primary Examiner-Robert M. Walker Attorney-White and Haefliger STEAM ABSTRACT: Steam is taken at a generated pressure e.g. from ncmms 6 Drawmg a-desalinization system and is altered in pressure for particular US. Cl 417/392 purposes e.g. to feed steam powered turbines at a single step Int. Cl F04b 35/00 or in multiple stages for example dividing a quantity of steam Field of Search 230/52,54, at an intermediate pressure into higher and lower pressure 56; 103/52, 54 portions.

STEAM ATYPRESSUPFP' STEAM COM RESSED VERY HIGH PRESSURE STAGE l METHOD AND APPARATUS FOR PRESSURIZING STEAM BACKGROUND OF THE INVENTION 1. Field of the Invention This invention has to do with manipulation of steam pressures for specific purposes. In a particular aspect the invention is concerned with obtaining steam at pressures adequate for running steam generators and from quite moderate pressure steam such as may be obtained by the evaporation under reduced pressures of water from openly exposed water bodies such as natural or artificial lakes and pools. Such processes produce steam at pressures too low for power generation through turbines.

In the arid areas of the world, there is need for a supply of desalinated water. While various schemes have been proposed to meet this need, they have in common the elimination of salt from water through vaporizing the water to steam and condensing. This vaporization is achieved generally through application of heat, derived from solar, mineral or nuclear sources, or more imaginatively through use of vacuum over a naturally warm water supply.

In my copending application Ser. No. 551,595, filed May 20, 1966, entitled WATER DESALINIZATION SYSTEM, now U.S. Pat. No. 3,450,602 issued June 17, I969, I have disclosed that ordinary sea water or other natural saline water supply may be vaporized without input of heat through application of vacuum. As there proposed, such water may be dearated and then vaporized by lowering water surface pressure to 28 mm. Hg. or less by virtue of heat content naturally occurring in such water. There results a vaporization of the water or steam at much lower temperatures than are typically associated with steam. Advantageously large artificial heat inputs and their associated capital and operating expense are avoided. There is need, moreover, for power to run the vacuum pumps and possibly for other purposes such as lighting or manufacturing operations in nearby areas. Particularly in remote or underdeveloped areas where power resources are limited, there is a need for both water and power.

2. Prior Art Prior attempts to obtain desired pressure steam to my knowledge have entailed the utilization of outside energy for compression or decompression purposes. In the present process the steam on hand is divided into a portion at the desired pressure and a second portion at some other pressure without the requirement of outside energy input. In this manner steam at turbine operating pressures may be obtained from a relatively low-pressure steam supply. Moreover, the invention takes heat out of steam, facilitating condensation thereof to water, which is useful in obtaining water in desalinization processes.

SUMMARY OF THE INVENTION It is a major objective of the present invention to provide method and apparatus for obtaining steam at a desired pressure by expanding or compressing a quantity of steam at another pressure and separating the steam, as expanded or compressed, to the desired pressure.

The invention has been occasioned by the need for raising the pressure of steam obtainable in a desalinization system to a level adequate to do work e.g. turbine generation of electricity, but the method and apparatus herein disclosed is generally applicable where a reduction or increase in steam pressure is desirable.

Accordingly, in a particular aspect, the invention provides a method for obtaining steam at a desired pressure in a system in which steam is generated at another pressure, which method includes alternately expanding and compressing steam in a correspondingly expanding and contracting zone, adding generated steam to said zone in timed relation to the expansion and contraction thereof to expand or compress the generated steam added and withdrawing steam from said zone in timed relation to said expansion or contraction of the zone to obtain steam in an expanded or compressed condition at a corresponding desired pressure greater or less than the pressure of the generated steam added to :said zone. The expansion of the zone may be induced by the introduction of the generated steam; similarly the contraction of the zone may be induced by the withdrawal of steam from the zone. In a common usage of the method, generated steam will be divided into separate relatively higher and relatively lower pressure portions with respect to the generated steam added by appropriately timed withdrawals of each portion from the zone. In this manner intermediate pressure steam may be initially expanded, on expanding the containing zone, and a portion thereof removed at a lowered pressure; the remaining portion of the steam is then compressed with the contraction of the zone to a higher pressure.

The expansion and contraction of the zone may be effected by the displacement of an inertial body within the zone with steam pressure. In a particular embodiment the displacement of the inertial body is accomplished by reaction of steam compressed to a relatively very high pressure by the body. Conveniently there are zones on either side of the inertial body and the body is displaced alternately in opposite directions to simultaneously expand steam on one side thereof in a first zone and compress steam on the opposite side thereof in a second zone. In this form of the invention the accelerating displacement of the body may be effected at alternately opposite sides of the body by the use of relatively high-pressure steam obtained by compression of trapped steam by the body at either end of the body oscillation.

Apparatus is provided for carrying out the method for providing steam at a desired pressure in a system in which steam is generated at another pressure which comprises a steam receiving chamber, means for alternatively expanding and contracting the volume of steam within the chamber, means for adding generated steam to the chamber in timed relation to steam volume expansion and contraction within the chamber to expand or contract the generated steam, means to withdraw steam from the chamber in timed relation to steam volume expansion and contraction to steam at a corresponding desired pressure greater or less than the pressure of the generated steam added to said chamber. The means for expanding and contracting the steam volume typically comprises a body reciprocally moveable through the chamber in response to steam pressure. The steam moveable body may be mounted to be displaced in alternately opposite directions by the pressure of compressed steam on either side thereof to simultaneously expand one chamber portion and contract another. In a specific embodiment there are provided means for introducing steam at the generated pressure on one side of the body being displaced to expand the introduced steam, means for withdrawing a portion of the expanded steam at a lower than introduced pressure, means: for returning the body to compress the remainder of the introduced steam to a desired higher than introduced pressure and means for withdrawing a first portion of the so-compressed steam, and means for retaining a second portion to be further compressed to return the body in the reverse direction.

BRIEF DESCRIPTION OF THE DRAWING The FIGS. la, lb, 1c, Id, 12 and lfd-epict schematically the present apparatus in various stages of its cycle of operation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing therefor, at Stage 1 FIG. la, a moveable body in the form of a piston 1.0 is at the lower end of chamber 12. Piston 10 rides in the chamber I2 in as close sealing relation as practicable to provide a minimum of blowby in conduct of the present method and a maximum of free movement ofthe piston.

The chamber 12 is provided with sets of valved steam lines at either end thereof. each of which lines may actually be one or more pipes. These sets of steam lines are functional duplicates. The depicted apparatus is useful for dividing intermediate pressure steam into higher and lower pressure steam.

Line 14, having valve 140, is connected to a supply of intermediate pressure steam (not shown) such as might be derived from an evaporative chamber in which saline water is boiled by a reduction in pressure within the chamber. Intermediate pressure steam will range in most cases between about 10 and 50 p.s.i., but may have a value between I and 500 p.s.i. or higher or lower. Line 18 having valve 180 is an outlet passage for steam of increased pressure produced in the apparatus as will be described. Line 20 approximately intermediate the ends of chamber 12 and having valve 200 is also an outlet passage positioned conveniently to remove decreased pressure steam from the chamber, although this line may be located at the chamber ends.

In the apparatus, a piston 10 is selected having a mass suitable to steam acceleration e.g. a weight of l to 5 and preferably about 2 pounds per square inch of exposed surface where the incoming intermediate pressure steam is at 16 pounds per square inch or 12.5 percent of that pressure. This mass may be varied between percent and 500 percent of the incoming steam pressure for variation in acceleration and momentum generated.

To facilitate overcoming inertia at first start up of the piston 10 on the beginning of a stroke very high-pressure steam may be introduced for a brief period. Thereafter the piston movement is provided by piston compressed steam. At Stage 1 valves 14a and 18a are closed. The piston 10 is displaced upward by the very much compressed steam in lowermost interior 22 of chamber 12. This steam is compressed in subsequent cycles by the return of the piston 10 thereagainst but at start up may be externally provided by means not shown. At Stage 2, FIG. 1b, valve 140, opens and intermediate pressure steam at a preselected pressure P e.g. 8 p.s.i. enters the lowermost chamber interior 22 from line 14. A predetermined quantity of steam is put through line 14 and valve 14a is then closed. This quantity of steam is mixed with the already present steam to continue to accelerate the piston 10 upwardly, with considerable momentum. As the piston 10 rises the chamber volume beneath the piston increases. Since the quantity of steam is fixed, and valve 14a is closed, the added steam expands to fill the available space. The steam temperature drops 'on the expansion, producing a lower temperature and lower I pressure steam. Shortly after the piston 10 reaches its apogee, shown as Stage 3, FIG. 1c valves 14a and 180 are closed and valve 200 opened. The lower pressure, lower temperature steam leaves the chamber 12 via line 20, e.g. at a pressure of P/2 (4 p.s.i.) or one half the input steam pressure. In Stage 4, FIG. 1d, the piston 10 now descends with the acceleration of gravity, driving expanded steam out through line for-part of its stroke e.g. one-fifth to four-fifths of the stroke and for the remainder of the stroke, Stage 5, FIG. 1e the piston compresses the remaining portion of the steam the decelerative forces needed to slow the motion of the piston e.g. to pressure 2 P (16 p.s.i.) or twice the input pressure where one-half the intermediate steam inputis compressed. At Stage 5; the valve 18a is opened and the increased pressure, increased temperature steam is taken off through line 18. At Stage 6 the piston continues past valve 180 to further compress steam remaining at 24, to reach a starting position for the nextcycle to commenced by the reaction of the steam at 24 which is highly compressed. The piston 10 thus bounces" upward to facilitate initiation of another cycle and to enable continuous oscillation of the piston with only the continuing addition of incremental enthalpy from P" pressure steam over that withdrawn in each cycle. In actual practice it is contemplated that the piston 10 will move rapidly between'extreme positions in the chamber 12. I

It is apparent that the lines and valves 141, 141a, 181, 181a etc. at the upper end of the chamber corresponding to lines and valves 14, 14a, 18 and 18a respectively may be operated to expand, remove and compress steam in the reverse of the lower end lines and valves as indicated. Thus while piston 10 is displaced to expand steam on one side, a portion of previously expanded steam may be compressed by the piston on the second side of the piston, as shown.

The feed steam e.g. in line 14 may vary in its pressure during feed due to temperature variation or other factor in which case the equivalent value of these pressures, having the effect of a single pressure supply,may be used in determining appropriate operation parameters. Similarly, the exhaust steam which may for example be used to raise the temperature of water, may be assigned a computed, equivalent value between the extreme values of a variable output steam.

The exhaust line 20 for lowered pressure steam can be connected to a further chamber as the intermediate pressure feed the amplified pressure steam (8 p.s.i.) being useful as a feed supply to the just-described chamber.

The lowered pressure steam is cooled and this output is obtained at an elevated level, providing water having an increased head, which is useful for power generation.

In a particular installation steam pressure amplification may include utilization of high pressure acceleration steam at p.s.i., 8 p.s.i, intermediate pressure steam supply from a desalinizing evaporator, 16 p.s.i. amplified pressure steam and 4 p.s.i. low-pressure steam.

The decrease in temperature with successive expansions is shown in the following Table where an initial input of 8 p.s.i. steam is put through 6 cycles of expansion and compression.

The invention also may be used to obtain an intermediate pressure steam output from a supply of low and high pressure steam. In this situation the introduction of low-pressure steam into a quantity of high-pressure steam has been troublesome. By expanding the high-pressure steam to a pressure at which low-pressure steam may be added, then compressing, the lowpressure steam may be incorporated in the high to obtain an intermediate pressure steam.

As indicated, the steam pressure device herein disclosed is desirably used in conjunction with a desalinization system where it is required to condense steam from a vapor generating step. The apparatus provides lowered pressure, cooler steam to be condensed and which may be obtained at higher levels, thus gaining head usable in power generation, and higher pressure steam which is more compact for handling and transportation and is useful for driving steam turbines or for other purposes.

I claim:

1. Method of obtaining steam at a desired pressure in a system in which steam is generated at another initial pressure that includes alternately expanding said steam to less than said initial pressure and compressing steam to greater than said initial pressure in a correspondingly expanding and contracting zone, adding a predetermined, fixed quantity of generated initial pressure steam alternately to said zones in timed relation to the expansion and contraction thereof to correspondingly expand or compress the generated steam added and withdrawing steam from said zones in timed relation to said expansion and contraction of the zones to obtain steam in an expanded or compressed condition at a corresponding desired pressure greater or less than the initial pressure of the generated steam added to each said zone.

2. Method according to claim 1 including inducing expanding the zone by said addition of generated steam.

3 Method according to claim 1 including inducing con tracting the zone by the withdrawal of steam therefrom.

4. Method according to claim I inducing dividing the added steam into separate relatively higher and relatively lower pressure portions with respect to the added steam. by appropriately timed withdrawals of each portion from said zone.

Sr Method according to claim 1 in which expansion and contraction of said zone is effected by displacing an inertial body within said zone with steam pressure.

6. Method according to claim 5 including also initiating reverse displacement of said inertial body with steam at relatively very high pressure just compressed by said body.

7. Method accordingto claim 5 including also displacing said inertial body alternately in opposite directions to simultaneously expand steam on one side thereof in a first zone and compress steam on the opposite side thereof in a second zone.

8. Method according to claim 7 including also alternately oppositely accelerating displacement of said inertial body with just-compressed steam at relatively high pressure.

9. Apparatus for providing steam at a desired pressure in a system in-which steam is generated at an initial pressure which comprises a steam receiving chamber, means defining said chamber and movable vertically for alternately expanding and contracting the volume of steam within the chamber, means for adding a predetermined, fixed quantity of generated steam to the chamber in timed relation to chamber volume expansion and contraction to expand or contract the added quantity of generated steam. means to withdraw steam from the chamber in timed relation to steam volume expansion and contraction to steam at a corresponding desired pressure greater or less than the pressure of the generated steam added to said chamber.

10. Apparatus according to claim 9 in which said expanding and contracting means comprises a body reciprocally moveable through the chamber in response to steam pressure.

1 1. Apparatus according to claim 10 including means for introducing steam on either side of said body to correspondingly displace the body.

12. Apparatus according to claim 11 including also means for introducing said-steam quantity to said chamber at said generated pressure on one side of the body to displace the body upward and expand the introduced steam, means for withdrawing from the chamber a portion of the expanded steam at lower than the initial pressure means for returning the body downward against steam not withdrawn from the chamber to compress the remainder of the introduced steam to a desired higher than initial pressure and means for withdrawing the so-compressed steam from the chamber. 

1. Method of obtaining steam at a desired pressure in a system in which steam is generated at another initial pressure that includes alternately expanding said steam to less than said inItial pressure and compressing steam to greater than said initial pressure in a correspondingly expanding and contracting zone, adding a predetermined, fixed quantity of generated initial pressure steam alternately to said zones in timed relation to the expansion and contraction thereof to correspondingly expand or compress the generated steam added and withdrawing steam from said zones in timed relation to said expansion and contraction of the zones to obtain steam in an expanded or compressed condition at a corresponding desired pressure greater or less than the initial pressure of the generated steam added to each said zone.
 2. Method according to claim 1 including inducing expanding the zone by said addition of generated steam.
 3. Method according to claim 1 including inducing contracting the zone by the withdrawal of steam therefrom.
 4. Method according to claim 1 inducing dividing the added steam into separate relatively higher and relatively lower pressure portions with respect to the added steam by appropriately timed withdrawals of each portion from said zone.
 5. Method according to claim 1 in which expansion and contraction of said zone is effected by displacing an inertial body within said zone with steam pressure.
 6. Method according to claim 5 including also initiating reverse displacement of said inertial body with steam at relatively very high pressure just compressed by said body.
 7. Method according to claim 5 including also displacing said inertial body alternately in opposite directions to simultaneously expand steam on one side thereof in a first zone and compress steam on the opposite side thereof in a second zone.
 8. Method according to claim 7 including also alternately oppositely accelerating displacement of said inertial body with just-compressed steam at relatively high pressure.
 9. Apparatus for providing steam at a desired pressure in a system in which steam is generated at an initial pressure which comprises a steam receiving chamber, means defining said chamber and movable vertically for alternately expanding and contracting the volume of steam within the chamber, means for adding a predetermined, fixed quantity of generated steam to the chamber in timed relation to chamber volume expansion and contraction to expand or contract the added quantity of generated steam, means to withdraw steam from the chamber in timed relation to steam volume expansion and contraction to steam at a corresponding desired pressure greater or less than the pressure of the generated steam added to said chamber.
 10. Apparatus according to claim 9 in which said expanding and contracting means comprises a body reciprocally moveable through the chamber in response to steam pressure.
 11. Apparatus according to claim 10 including means for introducing steam on either side of said body to correspondingly displace the body.
 12. Apparatus according to claim 11 including also means for introducing said steam quantity to said chamber at said generated pressure on one side of the body to displace the body upward and expand the introduced steam, means for withdrawing from the chamber a portion of the expanded steam at lower than the initial pressure means for returning the body downward against steam not withdrawn from the chamber to compress the remainder of the introduced steam to a desired higher than initial pressure and means for withdrawing the so-compressed steam from the chamber. 